Researchers put together a network of cardiac muscle cells stored in an inch-long silicone device that models human heart tissue, and demonstrated the viability of the system as a drug-testing platform for cardiovascular medications.
The device is an important step forward in the development of accurate, faster methods for testing drug toxicity, researchers commented.
“Ultimately, these chips could replace the use of animals to screen drugs for safety and efficacy,” said professor Kevin Healy from the University of California, Berkeley.
Predicting human reactions to new drugs involves a high failure rate when nonhuman animal models are used.
“It takes about 5 billion pounds on average to develop a drug, and 60 per cent of that figure comes from upfront costs in the research and development phase. Using a well-designed model of a human organ could significantly cut the cost and time of bringing a new drug to market,” said Healy.
The current alternative involving the use of heart cells derived from human-induced pluripotent stem cells – adult stem cells that can be directed to become different types of tissue.
The researchers designed their cardiac microphysiological system, or heart-on-a-chip, so that its 3-D structure would be comparable to the geometry and spacing of connective tissue fiber in a human heart.
In the future, this setup could also allow researchers to monitor the removal of metabolic waste products from the cells.
“This system is not a simple cell culture where tissue is being bathed in a static bath of liquid,” said study lead author Anurag Mathur, a postdoctoral scholar in Healy’s lab and a California Institute for Regenerative Medicine fellow.